Electronic integrating means for continuous variable quantities



Dec. 26, 1961 A. H. DlcKINsoN ELECTRONIC INTEGRATING MEANS FORCONTINUOUS VARIABLE QUANTITIES 5 Sheets-Sheet 1 Filed Nov. 27, 1953 B ZMJ J i HIS ATTORNEYS.

5 Sheets-Sheet 2 N vm Il .r .vm O @A 3N R m a., n SNj 1.1 -1 1 o E Lmfl.r .r l T K JN m2@ L. 1W m da m m l 109m @mm QQ .1 NN@ mm -i Sm :wm E vD T Ax m H. CM om om lm .nu R S n u u u ||n U m m m,... Il o c m @i M0mm .vmm n Om n WON m W No 6m Dec. 26, 1961 A. H. DlcKlNsoN ELECTRONICINTEGRATING MEANS F' OR CONTINUOUS VARIABLE QUANTITIES Filed NOV. 27.1953 Dec. 26, 1961 A. H. DlcKlNSoN 3,014,659

ELECTRONIC INTECRATINC MEANS FOR CONTINUOUS VARIABLE QUANIITIES 5Sheets-Sheet 5 Filed Nov. 27. 1953 lNvENToR.

ARTHUR H. DICKINSON @www l H l5 ATTONEYS.

Dec. 26, 1961 A. H. DlcKlNsoN ELECTRONIC INTEGRATING MEANS FORCONTINUOUS VARIABLE QUANTITIES 5 Sheets-$heet 4 Filed NOV. 27, 1953 mmmwww INVENTOR. ARTHUR H. DICKINSON BY a0/MJ I l., f J HIS ATTORNEYS.

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Dec. 26, 1961 A. H. DlcKlNsoN 3,014,659

ELECTRONIC INTECRATINC MEANS FOR CONTINUOUS VARIABLE QUANTITlEs FiledNov. 27. 1953 5 Sheets-Sheet 5 FIG.2

POWER SU PPLY INVENTOR.

ARTHUR l-LDICKINSON United States Patent Ciiice 3,014,659 Patented Dec.26, 1961 3,014,659 ELECTRGNIC INTEGRATING MEANS FR CON- TINUOUS VARIABLEQUANTITIES Arthur H. Dickinson, Greenwich, Conn., assignor toInternational Business Machines Corporation, New York, N Y., acorporation of New York Filed Nov. 27, 1953, Ser. No. 394,540 17 Claims.(Cl. 23S-152) The present invention relates to electronic measuring andindicating systems and, more particularly, to novel and improvedapparatuses for measuring and indicating the instantaneous values ofcontinuous varying phenomena, for integrating these values, and formanifesting the results of this integration in digital form.

Various types of electronic and electromechanical calculators andcomputers are currently being used for measuring and indica-ting thevalue of a variable quantity such as an electrical potential or aphysical displacement. Such a type of electronic measuring and recordingdevice is disclosed in a copending U.S. application Serial No. 270,411,filed February 7, 1952, by A. H. Dickinson, now Patent No. 2,872,670,and in United States Patents Nos. 2,700,750 and 2,717,994. The systemtherein disclosed operates by comparing a physical displacement or anelectrical potential proportional t the variable quantity being measuredto an incrementally increasing reference quantity and providing adigital manifestation of the value of the reference quantity when it isfound to be equivalent to the magnitude of the variable quantity.

The incrementally increasing reference quantity is derived from anelectronic circuit wherein pulses of a predetermined repetitionfrequency are fed through an electronic gating means into an electricalpulse counting device. A translator means converts the instantaneoussetting of the counting device into a reference potential having anamplitude proportional to the instantaneous setting of the pulsecounting device. This amplitude is continuously compared to a signalrepresentative of the variable quantity. When the reference signalreaches an amplitude equivalent to the value of the variable quantity,the gating circuit is closed and the counter circuit provides a digitalmanifestation of the amplitude of the reference signal. This type of asystem has been found to be very accurate, sensitive and reliable.However, there is no provision in such a system for integratinginstantaneous values of a variable quantity.

It is an object of the invention, accordingly to provide novel andimproved measuring and recording apparatuses of the aforementioned typewherein the instantaneous values of the variable quantity are integratedand a digital manifestation of the results of this integration is made.

Another object of the invention is to provide novel and improvedapparatuses for performing more than one order of integration ofcontinuous variable phenomena.

In accordance with the invention, electrical pulses having apredetermined repetition frequency may be generated by an electronicpulse generator and fed by means of a primary gating means to a registermeans such as an electronic pulse counting circuit. The instantaneoussetting of the electronic counting circuit may be translated into areference signal of incrementally increasing magnitude. This referencesignal may be continuously compared to an instantaneous sample of avariable quantity. When the reference signal reaches a magnitude equalto or in some predetermined proportion to the instantaneous sample, thecomparator operates to close the primary gating means, therebypreventing any further entries on the counting circuit. A value may thenbe manifested digitally by the counter that is either equal Cil to, orproportional to, the instantaneous value of the variable quantity. Aftera short period of manifestation, a feeding mechanism may supply the nextincremental portion of the continuous variable quantity to thecomparator and another cycle of measuring and indicating is initiated.

An entry may be made for each one of these measuring and indicatingcycles into a summation counter, wherein the results of the individualmeasuring and indicating cycles are integrated during a completeintegrating cycle. This summation counter is not reset until thecomplete integrating operation has been performed.

The preferred form of summation counter is electronic and is capable ofoperating either forwardly or backwardly. When the continuous varyingphenomena are negative, the summation counter operates backwardly and,when the phenomena are positive, the counter operates forwardly. Forexample, the summation counter may operate forwardly through a positiverange of say 0000 to +9999 or backwardly through a negative range from0000 to *9999. In order to accomplish this, the register means mustcount over a range equivalent to both the positive and negative rangesof the summation counter, .e., a range from 00000 to 19999. As theregister means commences counting from 00000, its value incrementallyincreases towards 10000 and the translator provides a step-by-stepincreasing reference potential. lf this potential in conjunction withthe potential of the instantaneous value of the variable quantity causesthe operation of the comparator before the register means reaches 10000,a secondary gate opens and permits pulses to operate the summationcounter backwardly, until the register means reaches 10000 (at whichpoint the counting operations cease).

On the other hand, if the comparator does not operate before theregister means reaches 10000, then, at such count, the secondary gatefor the summation counter opens and electrical pulses from the pulsegenerator cause the summation counter to operate forwardly. This actioncontinues until the translator reference potential and the potential ofthe variable quantity cause the operation of the comparator, suspendingfurther counting at a value equivalent or proportional to the variablequantity being sampled.

While the register means is reset at the end of every measuring andindicating cycle, the summation counter, as previously mentioned, is notreset until a complete integration has been effected. It is seen,therefore, that once each measuring cycle the summation counter receivesa count, which is added to the algebraic sum of all the previous counts.

A further embodiment of the invention provides a system wherein thesecond order of integration of a variable quantity can be achieved. Thissecond .order of integration is accomplished in a manner similar to theabovedescribed rst order of integration of the variable quantity` withthe exception that the entries on the rst summation counter at the endof each individual measuring and indicating cycle for the instantaneousvalues of the variable quantity are fed into -a second summationcounter, which provides a digital manifestation of the second order ofintegration of the variable quantity.

For a more complete understanding of the invention, reference may be hadto the following detailed description of the various embodiments of theinvention taken in conjunction with the accompanying figures of thedrawing, in which:

FlG. 1 is a schematic block diagram of an integrating system inaccordance with the invention;

FGS. 2 and 2.a are circuit diagrams of the electronic equipment includedwithin the dashed line 2 of FIG. 1;

FIG. 3 is an electrical circuit diagram of the equipment included withinthe dashed line 3 ofFIG. 1;

FIG. 4 is 4an electrical circuit diagram of either of the summationcounters S1 or S2 shown in the block diagram in FIG. 1; f

FIG. 5 Vis a schematic block diagram of another embodiment of theinvention which provides a second order of integration fora variablequantity; and

FIG. 6 is an electrical circuit diagram of the comparator shown in FIG.5.

Integrating system of FIG. v1"

Referring now to FIG. l, a pulse generator 10 supplies pulses having apredetermined repetition frequency to a primary gating circuit 11through a conductor 12. The output of the primary gating circuit 11 maybe connected by a conductor 15 to'a register means, for example, acounter and buffer circuit 14 which in turn may be connected by aconductor 16 t-o a translator unit 18. The output potential of thetranslator 18 may then be fed to two ccmparators C1 and C2 by means of aconductor The pulse generator 10, the` counter and buffer circuits 14,and the translator 18 may take the form of the similar circuitcomponents described in the aforementioned copending application SerialNo. 270,411.

Each of the comparators C1 and C2 may have separate sources 20 and 21,respectively, of signals representative of variable quantitiesyconnected to them. The outputs of the comparators C1 and C2 may beconnected through a conductor 22, a time delay device TDS and aconductor 24 to a secondary gate circuit 25. Y p

The input to the secondary gate circuit 25 may be connected to thepulsey generator 10 through a conductor 26, while the output of thesecondary gate `25 may be alternately connected to the summationcounters S1 and S2 through conductor means 28, a switching means CM and,conductor means 30.

The switching means CM may be arranged to alter;

nately enable the comparators C1 and C2 through conductor means 31.

The direction of operation of the summation counters S1 and S2 may becontrolled by a switching means BF through a conductor 32. The switchingmeans BF may in turn be controlled lby a control potential from thecounter and buffer circuits 14 through the conductor 34, which alsoserves to deliver a control potential from the counter and ybuffercircuit 14 to the secondary gate circuit 25.

A conductor 3S may serve to supply a control poten tial from thesecondary gate circuit 2S to the primary gate circuit 11. This controlpotential from the secondary gate circuit 25 may also be suppliedthrough the conductor 35 to a time delay device TD1. The time delaydevice TD1 may supply artirst control potential to the switching meansBF through a conductor 36 and a second control potential to a time delaydevice TD2 and the switching means CM through a conductor 38. The timedelay device TD2 may supply a control potential to the primary gatecircuit 11 via a conductor 39 and to a switching means CK via aconductor 40. The switching means CK may further be controlled by acontrol potential from the comparators C1 and C2 via a conducto-r 41.The switching means CK may then `be arranged to supply controlpotentials to the comparator circuits C1 and C2 via the conductors 42and 43, respectively.

peration of the system of FIG. 1

The variable quantity sources 20 and 21 supply variable electricalpotentials or physical displacements to their respective comparators C1and C2. These electrical potentials or physical displacements may berepresentative of any continuous variabler quantity, the instantaneousvalues of which are to be integrated. The comparators C1 and C2 operatein an alternate manner as will be seen from the following discussion.

During each cycle of operation of the comparators C1 and C2, anincremental instantaneous sample of the variable quantity is compared toa reference signal which is derived from the translator 18. It will beunderstood by those skilled in the art that these incrementalinstamane-ous samples must be taken at equal intervals along either atime axis or a displacement axis normal to the `amplitude displacementsof the instantaneous incremental values, so that'the count manifested bythe summation ccunters S1 and S2 will be representative of theintegration of the instantaneous values over the total period.

The pulse generator 10 serves to generate electrical pulses at apredetermined repetition frequency. The

y primary gate circuit 11 is manually enabled at the start of a completeintegration cycle so as to initially pass the electricalpulse output ofthe pulse generator 10 to the counter and buffer circuits 14.

As d1scussed 1n detail, for example, in the aforementioned patents andcopending application Serial No. 270,-

411, the register means or counter circuit 14 may comprise a pluralityof banks of series connected double` stability trigger circuits. Each ofthe banks of trigger circuits corresponds to a different denominationalorder of magnitude. For example, five banks of trigger circuits maybeutilized, corresponding to the denominational orders of units, tens,hundreds, thousands, and ten thousands. Inl the preferred embodiment,only one trigger circuit is used inthe ten thousand order. Thus acounting range of 00000 to 19999 is provided by the counter or registermeans 14.

As further described in the aforementioned patents and applicationSerialv No. 270,411, a signal representative of the stability positionof each of the trigger circuits in the counter or register means 14 issupplied through a buffer unit to the translator 18. The buffer unitfunctions to maintain the individual control signals from the triggercircuits at uniform levels in order to secure dependability in theoperation of the system. However, under some circumstances it may befound that satisfactory results can be achieved without the utilizationof a buffer unit intermediate the counter circuit or register means 14and y the translator unit 18. y Y

' reference signal correspond to the discrete electrical pulses beingfed from the pulse generator 10 throughv the primary gate circuit 11 tothe counter circuit or register means 14.

Since the instantaneous samples of the variable quantities may be eitherpositive or negative, it is necessary to select a reference point in therange of the counter circuit or register means y14 as a zero value. Inthe preferred embodiment, this value is selected as 10000. Therefore, anegative range from 00000 to 10000 and a positive range from 10000 to19999 isprovided. Accordingly, it is necessary to arrange the comparatorcircuits C1 and C2 so that the zero values of the variable quantitiessupplied by the sources 20 and 21 will coincide with the zero value ofthe reference signal supplied by the translator unit 18. i

At the initiation of the complete integrating cycles for the summationcounters S1 and S2, and the comparators C1 and C2, the secondary gatecircuit 25 is closed, the switching circuit CM is conditioned so as toenable the comparator C1,.in preference to the comparator C2, and thesummation counter S1, in preference to the summation counter S2, and theswitching circuit BF is condiari-14,659

tioned so that both the sunmmation counters S1 and S2 will operatebackwardly.

Therefore, when the complete integrating cycle is initiated the primarygating circuit 11 starts to pass electrical pulses from the pulsegenerator to the counter circuit 14 and the instantaneous settings ofthe counter circuit 14 are converted by the translator unit 18 into areference signal. The amplitude of the reference signal is thencontinuously compared to the instantaneous sample of the variablequantity by the comparator C1.

If the value of the instantaneous sample of the continuous variablequantity is negative, the comparator C1 will open the secondary gatecircuit through the time delay device TD3 before the reference signalreaches its zero value, corresponding, to the count 10000 on the countercircuit or register means 14, and switch the switching device CK to analternate condition whereby it discharges the comparators C1 and C2. Theopening of the secondary gate circuit 25 permits electrical pulses fromthe pulse generator 10 to pass through it to the switching circuit CM.As aforementioned, the switching circuit CM is initially conditioned sothat the summation counter S1 is enabled in preference to the summationcounter S2. Thus the electrical pulses passing through the secondarygate 25 are directed to the summation counter S1. Further, since theswitching circuit BF has initially conditioned the summation counter S1to operate in a backwardly direction, the electrical pulses arenegatively counted on the summation counter.

This counting operation of the summation counter S1 continues until thecounter circuit or register means 14 reaches its mid-point 10000, whichis equivalent to the Zero value of the reference signal. The tenthousand count for the counter circuit 14 will occasion a change in thestability condition of the single trigger circuit in the ten thousandorder bank. This change in the stability condition produces a controlpotential or pulse which passes through the conductor 34 to close thesecondary gate circuit 25. This pulse also serves to switch theswitching circuit BF to condition the summation counters S1 and S2 tooperate in a forwardly direction. The reason for this last mentionedoperation will become apparent in the following discussion relating topositive quantities.

If, on the other hand, the value of the instantaneous sample of thecontinuous variable quantity is positive, the comparator C1 will notoperate until after the counter circuit or register means 14 exceeds acount of 10000. However, when the count of 10000 is reached by thecounter circuit 14, certain changes must be effected in the system toenable it to count forwardly. are effected by the control pulse producedby the change in the stability condition of the single trigger circuitin the ten thousand order bank.

Since the secondary gate circuit 25 has not been previously opened inthis measuring cycle, the control pulse from the counter circuit 14passes over the conductor 34 and opens the secondary gate circuit 25.This control pulse also serves, as previously mentioned, to switch theswitching device BF to condition the summation counters S1 and S2 tooperate in a forwardly direction.

When the secondary gate circuit 25 is opened, electrical pulses from thepulse generator 10 are passed through the conductor 26, the secondarygate circuit 25, the conductor 28, the switching means CM, the conductorto the summation counter S1, which is operating in a forwardlydirection. Thus the counter circuit 14 and the summation counter S1 areeach counting in a forwardly or additive direction.

When the reference signal from the translator unit 18 reaches a valuecorresponding to the value of the instantaneous sample of the continuousvariable quantity, the comparator C1 operates and closes the secondarygate circuit 25 through the time delay device TD3. The comparator C1also switches the switching device CK to an These changes i 6 alternatecondition whereby it C1 and C2.

When the secondary gate circuit 25 is closed by the control potentialfrom the counter circuit 14 or from the comparator C1, a control signalis sent via the conductor 35 from the secondary gate circuit 25 todisable or close the primary gate circuit 11. This control signal isalso fed to the time delay device TD1.

Since the switching circuit BF must be returned to its originalcondition so as to condition the summation counters S1 and S2 to operatebackwardly at the start of the next individual measuring cycle, acontrol potential or pulse is fed from the time delay device TD1 throughthe conductor 36 to the BF switching device.

A second control signal is also derived by the time delay device TD1 andis transmitted through the conductor 38 to initiate the operation of thetime delay device TD2 and to switch the switching device CM. The outputof the time delay device TD2 is fed through the conductor 39 to theprimary gate circuit 11 to initiate the next individual measuring cycle.At the same time, the output control potential from the time delaydevice TD2 is fed over the conductor 40 to the switching circuit CK toreturn it to its initial position, thereby enabling the comparatorcircuits C1 and C2 via the conductors 42 and 43.

The control signal on the conductor 38 from the time delay device TD1causes the switching means CM to switch its position so as to enable thecomparator circuit C2 and the summation counter S2 in preference to thecomparator circuit C1 and the summation counter S1.

Thus the circuit elements of the system are prepared for the nextindividual measuring cycle, which is initiated by the control signalover the conductor 39 to the primary gate circuit 11. At the end of thisnext individual cycle, in which an instantaneous sample of the variablequantity from the source 21 is compared in the comparator circuit C2 andthe value recorded in the summation counter S2, the control signal fromthe time delay device TD1 again returns the switching device BF to itsinitial position in preparation for another individual measuring cycle.This control signal also reverses the switching means CM so as to enablethe comparator C1 and the summation counter S1 in preference to thecomparator C2 and the summation counter S2.

The control signal from the time delay device TD2 then completes theenabling of the comparator C1 through the switching circuit CK and theconductor 42. lt further initiates the next individual measuring cycleby opening or enabling the primary gate circuit 11 by a control signalover the conductor 39.

At the end of the second individual measuring cycle and all othereven-numbered individual measuring cycles, the switching means CK willalso function to vary the feed of the variable quantities from thesources 20 and 21 to the comparators C1 and C2 so that the nextincremental instantaneous values of the variable quantities will besampled during the next odd and even cycles, respectively.

Thus it is apparent that the system of FIG. 1 provides an apparatuswhereby the instantaneous values of two diiferent variable quantitiesmay be integrated in the alternate measuring cycles of the device.

Let us now consider the detailed circuits for preferred embodiments ofthe various system components shown in FIG. l which are not described indetail in the aforementioned copending application. As an aid inunderstanding the operation of the system, the triode section of each ofthe trigger circuits in FIGS. 2, 2a, 3 and 4, which is initiallyconductive at the start of the overall integrating cycle, is shaded.Further, typical waveforms representative of signals to be carried overcertain of the conductors have been placed adjacent to these conductors.

The electronic circuits in FIGS. 2, 2a, 3, 4 and 6 are discharges thecomparators energized from a plate supply` bus 201 connected to asuitable source 198 of positive plate potential, a bus 202 connected toa ground 199 or other suitable reference point and a negative bias bus203 connected to a suitable negative biasing potential source 200.

Component control circuitsl shown iny FIGS. 2 `and 2A The primary gatecircuit 11 may include a pentodetype electron discharge device 205connected as a gating tube and having an anode 206, a control grid 208and a grid 209; and an electron discharge device 210 having a left-handtriode section 211 and a right-hand triode section 212 with controlgrids 214 and 215, respectively, and connected as a double-stabilitytrigger circuit. The control grid 208 of the gating tube 205 may beconnectedl through a conductor 216 to the control grid 215 of theright-hand triode section 212.

A manual starting circuit for the primary gate circuit 11 may comprisetwo series resistors 218 and 219, a capacitor 220 and asingle-pole-double-throw switch 221. The series resistors 218 and 219may be bridged between the positive bus 201 and the negative biasing bus203. The capacitor 220 may be connected between the negative biasing bus203 and the movable contact of the switch 221. In its normal position,the switch 221 may connect the capacitor 220 to a point intermediateNthe resistors 218 and 219. In its operative position, the switch 221may connect the capacitor 220 to the control grid 215 of the right-handtriode section 212.

The switching circuit CM may include an electron dis'- charge device 225having a left-hand triode section 226 and a right-hand triode section227. The left-hand triode section 226 may include an anode 228 and acontrol grid 229. The right-hand triode section 227 may include acontrol grid 230. The electron discharge device 225 is connected as aconventional double-stability trigger circuit.

The switching means CM may also include a pentodetype electron dischargedevice 231 having an anode 232, a control grid 233 and another grid 234,and connected as a gating tube. The control grid 233 of the gating tube231 may be directly coupled to the control grid 229 of the left-handtriode section 226. Another pentodetype electron discharge device 235may be included in the switching means CM and may have an anode 236, acontrol grid 237 and another grid 238. The control grid 237 of thegating tube 235 may be directly coupled to the control grid 230 of theright hand triode section 227. The anode 236 of the gating tube 235 maybe connected through the conductor 30 to one of [the summation countersS1 or S2, preferably the summation counter S1. The anode 232 of thegating -tube 231 may be connected through the conductor 30" to ftheother of the summation counters S1 and S2, preferably S2. 2

The control grids 229 and 230 of the left hand triode section 226 andthe right hand triode section 227, respectively, may be capacitivelycoupled to the conductor 38 leading from the output of the time delaydevice TD1. The control grid 229 may also be connected through aconductor 31" to the comparator C2 and the control grid 230 may beconnected through the conductor 31 to the comparator C1. The grids 234and 238 of the gating tubes 231 and 235, respectively, may be connectedthrough the conductor 28 to the output of the secondary gate circuit 25.

The switching circuit BF may include an electron discharge device 250connected as a conventional doublestability trigger circuit and having aleft hand triode section 251 and a right hand triode section 252. Theleft hand triode section 251 may include a control grid 254. The righthand triode section 252 may include a control grid 255. A triode-typeelectron discharge device 258 having a cathode 260 and a control grid261 may be conneoted in a cathode follower circuit across the busses 201and 203 with an output resistor 262 connected be- 8 tween the cathode260 and the negative bias bus 203. The control grid 261 may be connectedby a variable tap on a biasing resistor 263 to the control grid 254 ofthe left hand triodeV section 251, which may be connected between thecontrol grid 254 and the negative bias bus 203.

in a similar manner, a triode-type electron discharge device 259having'a cathode 265and a control grid 266 may be connected in a cathodefollower circuit across the busses 201 and 203. An output resistor 268may be connected between the cathode 265 and the negative biasing bus203. The control grid 266 of the discharge device 259 may be connectedthrough a variable tap to a resistor 269 serving as a biasing resi-Storbetween the control grid 255 of the right hand triode section 252 andthe negative biasing bus 203. The cathodes 260 Vand 265 of the triodes258 and 259 may be connected through conductors 32 and 32, respectively,to the 'summation counters S1 and S2 in order to condition the summationcounters for either forward or backward operation, as will be describedin greater detail hereinafter.

F'ne time delay device TD1 may comprise an electron discharge deviceconnected as a single-stability trigger circuit with a predeterminedtime constant and having a left hand triode section 281 and a right handtriode section 282, The left hand section 281 may include an anode 283and a control grid 284. The right hand section 282 may include an anode285 and a control grid 286. The anode V283 of the left hand section 281may be connected to the plate supply bus 201 through a load resistor 288having an intermediate tap connected to the conductor 38 leading to thetime delay device TD2 and the switching circuit CM. The anode 235 may becapacitively coupled to a conductor 291 leading to a control grid 292 ofa triode-type electron discharge device 294 having an anode 295. Thecontrol grid 292 may be biased by connection to an intermediate tap on aresistor 296 bridged between the ground bus 202 and the negative biasingbus 203. A resistor 29S may serve as a load resistor for the electrondischarge device 294 and be connected between the plate supply bus 201and the anode 295. A variable tap 299 on the load resistor 298 may beconnected to the conductor 36, which is capacitively coupled to thecontrol grid 255 of the right hand triode section 252 of the BF triggerdevice 250.

The time delay device TD2 may comprise an electron discharge devicehaving a left hand triode section 301 and a right hand triode section302 connected as a singlestability trigger circuit having apredetermined time constant. The left hand triode section 301 mayinclude an anode 304 and a control grid 305. A load resistor 306 may beconnected between the anode 304 of the left hand triode section 301 andthe plate supply bus 201 and have an intermediate tap thereon connectedthrough the conductor 39 to the primary gate circuit 11 and through theconductor 40 to the switching circuit CK. The control grid 305 of theleft hand triode section 301 may be capacittively coupled to theconductor 38 leading to the load resistor 288 of the time delay deviceTD1..

The time delay device TDS may comprise an electron discharge device 310having a left hand triode section 311 and a right hand triode section312, connected as a singlestability trigger circuit having apredetermined time constant. The left hand Vtriode section 311 mayinclude an anode 314 and a control grid 315. A resistor 316 may beconnected between the anode 314 and the plate supply bus 201 and have atap thereon connected by the conductor 24tto the secondary gate circuit25. The control grid 315 of the left hand triode section 311 may becapacitively coupled to the conductor 22 leading from the outputs of thecomparators C1 and C2.

The secondary gate circuit 25 may comprise an electron discharge device320 having a left hand triode Section l321V and a right hand triodesection 322, con- L I) nected as a double-stability trigger circuit. Theleft hand triode section 321 may have an anode 324 and a control grid325. The right hand triode section 322 may include a control grid 326.The control grids 325 and 326 may be capacitively coupled to theconductor 34 leading to the load resistor 316 of the time delay deviceTD3. A resistor 328 may be connected as a load resistor between theanode 324 and the plate supply bus 201 and have a tap thereon connectedthrough the conductor 35 to the time delay device TD1 and the primarygate circuit 11.

A pentode-type electron discharge device 330 may be included in thesecondary gate circuit 25 as a gating tube and have a control grid 33-1,another grid 332 and an anode 334. The control grid 331 may be directlycoupled to the control grid 326 of the right-hand triode section 322 ofthe device 3120. A triode-type electron discharge device 338 having ananode 340 and a control grid 339 may be connected as an inverter in theoutput circuit of the gating tube 330. This may be accomplished byconnecting the control grid 339 of the invert-er 338 to a variable tapon a resistor 341, which has one terminal connected to the ground bus202 and the other terminal connected through a capacitor 342 to theanode 334. rI'he inverted output of the gating tube 330 may be thencapacitively coupled to the conductor 28 leading to the switchingcircuit CM.

Details of compamtors C] and C2, and switching circuit CK The comparatorC1 and its associated source 20 of a variable quantity may havesubstantially the same structure as the comparator C2 and the source 21of a variable quantity. Accordingly, corresponding structure in each ofthe comparators C1 and C2 and the sources 20 and 21 have been designatedby the same reference numerals, with those elements in the comparator C2being identified by a primed number. Therefore, in discussing thestructural arrangement of the elements in the circuit diagram of FIG. 3,reference will be had only to the source 20 and the comparator C1, itbeing understood that the description is equally applicable to thesource 21 and the comparator C2.

The source 20 may comprise a tape or film 400 having a curve 401 thereonrepresentative of some particular intelligence or signal. The tape 400may be driven by a feeding mechanism 402. A stylus 404 may be adapted ina conventional manner to follow the curve 401 on the tape 400. ri`husthe stylus may be displaced mechanically as a function of the magnitudeof the curve displacement from a predetermined zero position or datumline.

In order to convert the mechanical displacement of the stylus 404 intoan electrical quantity, the stylus 404 may be connected to a variabletap 405 on a potentiometer 406, which may be energized from a suitablesource of electrical energy 408. The variable tap 405 may be connectedby a conductor 409 to a control grid 410 of a pentode-type electrondischarge device 411 having an anode 412, a cathode 414, and a screengrid 415. The cathode 414 may be connected through a cathode biasingresistor 416 to the ground bus 202. The anode 412 may be connected by aconductor 418 through a resistor 419 to a control grid 420 of a gaseousdischarge type, electron discharge device 421, having an anode 422 and acathode 424. The anode 422 may be connected through a load resistor 425to a high voltage plate supply bus 426. The high voltage plate supplybus 426 may be connected to the positive terminal 42S of a suitable highvoltage source having a value greater than the source 198.

The output of the translator unit 18 may be connected through anelectron discharge device 430 to the cornparators C1 and C2. Theelectron discharge device 430 may have a left hand triode section 431associated with the comparator C1 and a right hand triode section 431associated with the comparator C2. Each triode section may comprise ananode 432, a control grid 434 and a cathode 435. The conductor 19leading from the trans- 10 lator unit 18 may be connected to the controlgrid 434. The cathode 435 may be connected through a cathode biasingresistor 436 to the ground bus 202 and to the control grid 420 of thegaseous discharge device 421 through a resistor 438, a conductor 439,and the resistor 419. The anode 432 may be directly coupled to the highvoltage plate supply bus 426. The conductor 419 may also be connected toa means for preventing spurious, relatively short fluctuations of higherpotentials from causing premature operation of the comparator unit. Thislast-mentioned means may preferably include a tetrodetype electrondischarge device 440 and a smoothing capacitor 441 arranged in a mannerfully described in the aforementioned copending application Serial No.270,411.

A potential stabilizing circuit for the gaseous discharge device 421 mayinclude a resistor 446 and a pentode-type electron discharge device 445bridged from the high voltage plate supply bus 426 to the ground bus202. As described in greater detail in the aforementioned copendingapplication Serial No. 270,411, a variable resistive network 448 may beconnected between a source 449 of positive potential and the groundreturn bus 202 to a screen grid 450 of the electron discharge device445. The cathode 424 of the gaseous discharge device 421 may be coupledto a point intermediate the resistor 446 and the electron dischargedevice 445.

An output signal may be taken from the gaseous discharge device 42dacross the resistor 451 by means of a capacitor 452 connected to thecathode 424 and leading to a grid 454 in a pentode-type electrondischarge device 455, having an anode 456, a control grid 458, and acathode 459. The cathode 459 may be directly coupled to the groundreturn bus 202 and the anode 456 may be coupled to the plate supply bus201 through a load resistor 460. The load resistor 460 may be common tothe anode 456 in the comparator C1 and the anode 456 in the comparatorC2. Further, the anodes 456 and 456 may be directly coupled to theconductor 22 leading to the time delay device rl`D3.

in order to maintain a linear relation between the input signal on thecontrol grid 410 of the discharge device 411 and the output applied tothe gaseous discharge device 421, the relative potential differencebetween the cathode 414 and the screen grid 415 may be maintainedsubstantially constant in the manner described in the aforementionedcopending application Serial No. 270,411. For example, the conductor 409leading from the variable tap 405 on the potentiometer 406 may also beconnected to a control grid 461 of a tetrode-type electron dischargedevice 462 having an anode 464 and a cathode 465. The cathode 465 may becoupled to the ground return bus 202 through a cathode biasing resistor466. The anode 464 may be directly coupled to the high voltage platesupply bus 426. A voltage regulating device 468, which may be of anysuitable conventional type, having a cathode 469 and an anode 470, and aresistor 471 may he bridged across the electron discharge device `462.More particularly, the cathode 469 ofthe voltage regulating device 468may be connected to the cathode 465 of the electron discharge device 462and the plate 470 of the voltage regulating device 468 may be connectedthrough a conductor 472 to the resistor' 471 and thence to the highvoltage plate supply bus 426. The anode 470 of the voltage regulatingevice 46S may also be directly coupled to the screen grid 415 of theelectron discharge device 411.

A triode-type electron discharge device 478 having an anode 479, acontrol grid 480 yand a cathode 481 may be connected across the gaseousdischarge device 421, in order to extinguish the device 421 in themanner described in the aforementioned application Serial No` 270,411.More particularly, the anode 479 of the triode 478 ma be directlycoupled to the anode `422 of the gaseous discharge device 421. Thecathode 481 may be directly coupled to a suitable source of referencepotential, preferably a source of positive potential 482 having apotential less than the high positive potential of the bus 426. `Thecontrol grid 480 of the triode 478 in the comparator C1 may be connectedthrough a circuit including the conductors 42 and 42a to the switchingcircuit CK. Similar'- ly, the control grid 480 of the triode `478' inthe comparator C2 may be connected through a circuit including theconductors 43 and 42a to the switching circuit CK.

The switching circuit CK may comprise an electron dis-r charge device485 having a left-hand triode section 436 and a right-hand triodesection (87, connected as a conventional double-stability triggercircuit. The left-hand triode section 486 may include a control grid 483and 'the right-hand triode section 487 may include a control grid '489land an anode 490. The conductor 42a may be directly coupled to theanode i90Y of the right-hand triode section 487. The conductor 40leading yfrom the time delay device TD2 in FIG. 2 may be capacitivelycoupled to the control grid 48S of the left-hand triode section 48d. Theconductor 41 leading from the anodes 456 and 456' may be lcapacitivelycoupled to the control grid 489 oi the right-hand triode section `487.

A further element in the switching circuit CK mayv include apentode-type electron discharge device 492 having an yanode 493, a grid@94, and a control grid 495. A conductor 499 leading from the anode 228inthe lefthand triode section 226 of the switching means CM in FIG. 2may be capacitively coupled to the grid 494. A conductor 500 leadingfrom the anode 285 in the righthand triode section 282 of the time delaydevice TD1 may be capacitively coupled to the control grid 495. Theanode y493 may be coupled to the plate supply bus 201 through aconductor 496, an operating coil i157 in the feeding mechanism 402 forthe sources and 21 of variable quantities, and the conductor 498.

Detailed operation of the integrating system of FIG. I in view of thespecific exemplary circuit components disclosed in FIGS. 2, 2A and 3 Letus rst consider the initial conditions of each of the circuitcomponents. As shown inA FIG. 2, the primary gate circuit 11 is closed.This is duetto the fact that the left-hand triode section 211 isconductive `and the potential on the control grid 208, which is directlycoupled to the control grid 215, is at the least positive of two potentials, whereby the grid 208 is negatively biased to block the passageof positive pulses appearing on the grid 209. The switch 221 normallyconnects the capacitor 220 to the intermediate point between theresistors 218 and 219, whereby the capacitor is maintained charged to apotential sufficient to partially enable the gating tube 205 and triggerthe trigger circuit 210.

In the secondary gatey circuit 25, the left-hand triode 321 of thedouble stability trigger circuit 326 is conductive and the control grid331, which is directly coupled to the control grid 326 of the right-handtriode section 322, is suilciently negatively biased toblock the passageof positive pulses from the pulse generator 10 which appear on the grid332 of the gating tube 330. Thus, the secondary gate circuit 25 is alsoinitially closed.

As for the switching device BF, it is seen in FIG. 2 that the left-handtriode section 251 is initially conductive and the right-hand triodesection 252 is initially nonconductive. Under these conditions, thecontrol grid 254 in the left-hand triode section 251 will be at a morepositive potential than the control grid 255. Therefore, there will be agreater voltage drop across the resistor 263 than across the resistor26a. That being true, the potential on the grid 261 of the triode 258 ishigher than the potential on the grid 266 of the triode 259, and thetube 2578 is more conductive than the tube 259'. In these circumstances,the voltage drop across the cathode biasing resistor 262 of the tube 258will Ybe greater than the voltage drop across the cathode biasingresistor 263 of the triode 259 and the potential on the conductor 32will be more positive than the potential on the conductor 32".

, 12 As will be explained in detail hereinafter, this potentialarrangement on the conductors 32 and 312" serves to conditionthesummation counters S1 and S2 to operate in a backwardly direction, i

As for the switching means CM, the double-stability trigger circuit 225is initially conditioned so that the righthand triode section 227 isconductive and the potential of the grid 230 is more positive than thepotential of the grid 229. Thus, the control grid 237 of the right-handgating tube 235, which isdirectly coupled to the control grid 230 of theright-hand triode section 227, ismore positive than the controlgrid 233of the left-hand gating tube 231. ln fact, the potential o-n the controlgrid 237 is suicient to partially enable the right-hand gating tube 235so that the presence of positive pulses on the Igrid 23S willrcause theright-hand gating tube 235 to conduct and pass the positive pulses asnegative pulses over the conductor 30' to the summation counter S1.Therefore, the initial condition of the switching means CM is such thatthe summation counter S1 is selected in preference to the summationcounter S2 to receive pulses from the secondary gate circuit 25, whenthe secondary gate circuit 25 is opened.

The comparator C1 is also initially selected to operate in preferencetothe comparator C2, by means of the switching means CM. The potentialon the conductor 31', which is connected to the control grid 230 of theright-hand triode'section 227 of the switching means CM,V is morepositive than the corresponding potential on theV conductor 31"connected to the control grid 229 of ther left-hand triode section 226.The conductor '31 is connected to the control grid 458 of the dischargedevice 455 in the comparator C1 and the conductor 31 is connected to thecontrol grid 458 in the discharge device 455 in the comparator C2.Therefore, the more positive potential of the conductor 31 and theVcontrol grid `458 partially enables the discharge device 455 so that anegative pulse will be transmitted over the conductor 22 to the timedelay device TDS upon the tiring of the gaseous discharge tube 421 ofthe comparator C1.

As for the time delay devices TD1, TD2 and TDS, it is seen that they areeach initially in `their stable state with the left-hand triode sections281, 301 and 311, respectively, conducting.

At the start cfa complete integrating cycle, the starting switch 221 inthe primary gate circuit 11 Iis manually moved-from its position sho-wnin FIG. 2 to its operative position, contacting the control grid 215 inthe right-hand triode section 212 of lthe double-stability triggercircuit comprising the electron discharge device 210, 4and the controlgrid 215 becomes suiciently positive to trigger the trigger circuit 210.Thus, the right-hand `triode section 212 becomes conductive, theleft-hand triode section 211 becomes nonconductive, and the control grid215 of the right-hand triode section 212 becomes more positive. Sincethe control grid 208 is directly coupled to the control grid 215 throughthe conductor 216, the increase in potential on the control grid 215 isaccompanied by a positive increase in potential on the control grid 203of the gating tube 205, producing a Zero bias on the grid 208 andpartially enabling the gating tube 205.

Thus, the primary gate circuit 11 is opened and passes the constantrepetition frequency pulses generated by the puise generator 10. Thesepulses first appear on the grid 209 of the gating tube 205 as positivepulses and then appear as negative pulses in the conductor 15 by meansof which they `are fed to the counter and butler circuit 1d (FIG. l). Asdescribed in the aforementioned -copending application Serial No.270,411, these negative puises cause 4the operation of the countercircuit 14 and an incrementally increasing count is manifested by thecounter 14 for each of the negative pulses passed by the primary gatecircuit 11. The count present in the counter and bulier circuit 14 isthen converted by the translator unit 18 into an incre-mentallyincreasing reference signal having a value proportional to the countmanifested by the counter and butler circuit 14.

As previously described with relation to the system of FIG. 1, thecounter or register 14 may be adapted to count from 00000 to 19999 andmay include tive denominational orders or banks of trigger circuits,namely, units, tens, hundreds, thousands and ten thousands.

V hen the last trigger circuit in the thousand order is returned to itsGti condition, a negative pulse is supplied to the single triggercircuit in the ten thousand order (i.e., counting from 09999 to 10000).rhe negative pulse also acts to open the secondary gate circuit andtrigger the switching device BF, in a manner as will be hereinafterdescribed.

As explained in detail in the aforementioned copending applicationSerial No. 270,411, the bias potential upon the cathode 424 (FIG. 3) ofthe gaseous discharge device 421 in relation to the anode 42.2 isadjusted by means of the variable resistive network 44S, so that thegaseous discharge device 421 is bareh extinguished, when the register orcounter 14 is set at 00000 and the potentiometer 405 is zat apredetermined reference potential with respect to the ground bus 202,and will tire when the reference potential developed by the translatorunit 1S produces a small increase in potential of the control grid 420with respect to the ground bus Since the setting of the stylus 404causes a corresponding mechanical displacement of the variable tap 405of the potentiometer 406, the electrical potential on the conductor 409is proportional to the displacement of the potentiometer variable tap405. Thus, for any one setting an electrical potential is placed on theconductor 409 corresponding to an instantaneous sample ci a. variablequantity represented by the curve 401 on the tape 400. This potentialappears on the grid 410 and causes the conductivity of the electrondischarge device 411 to be proportionate to the displacement. When thereis a displacement ot' the stylus 404 following the curve 401 from theaforementioned reference value ot the potentiometer 406, the tube 411 ismade more conductive. Thus the zero bias potential present on thecontrol grid 420 of the gaseous discharge device 421 is reduced by anamount proportionate to the displacement o the curve 401.

The incrementally increasing reference potential supplied by thetranslator unit 18 is fed over the conductor 19 to the control grid 434of the electron discharge device 430. A corresponding incrementallyincreasing reference voltage is developed across the cathode outputresistor 436 and fed through the resistor 433, the conductor 439 and theresistor 41S*d to the control grid 420 of the gaseous discharge device421. Thus the incrementally increasing voltage across the cathodebiasing resistor 436 serves to incrementally return the potential of thecontrol grid 420 of the gaseous discharge device 421 to the tiringpotential.

When the reference potential reaches a value equal or proportional tothe instantaneous sample of the variable quantity as detected by thestylus 404, the gaseous discharge tube 421 will be red. When the gaseousdischarge device 421 tires, the potential of the cathode 424 becomessubstantially more positive. Since the grid 454 of the discharge device455 is capacitively coupled through the capacitor 452 to the cathode424, the tube 455 becomes conductive. A voltage drop is produced acrossthe resistor 460, thereby substantially lowering the potential of theanode 456 and creating a negative-going pulse in the conductor 22 whichtriggers the single-stability trigger circuit 310 in the time delaydevice T133.

1n order to have both positive and negative excursions by the curve 401on the tape 400 of the sources 20 and 21 of variable quantities, a zerodatum line must be elected for te tape. The initial adjustment cf theb`as potential by the network 448 must be made so tha the datum line ontape 460 corresponds to the point at which 14 the device 421 will tirewhen the counter 14 has a count of 10000.

Before continuing with the discussion of the effect of triggering thetime delay device TDS, let us first assume that the instantaneous sampleof the variable quantity is negative relative to the zero datum line.Under these circumstances, the counter and butter circuit 14 will nothave arrived at a count of 10000. Therefore, the secondary gate circuit25 and the switching device BF are still in their initial conditions.

When the gaseous discharge tube 421 tires upon the coincidence in valuebetween the reference signal fed over the conductor 19 from thetranslator unit 1S and the instantaneous sample fed over the conductor409, a nevative pulse is transmitted over the conductor 22 to thecontrol grid 315 (FG. 2a) of the left-hand triode section of the timedelay device TDS. This negative pulse triggers the time delay device TDSto its unstable condition, where the right hand triode section 312 isconductive. After a predetermined period of time, the trigger circuit3161 automatically switches back to its stable condition, where the lefthand triode section 311 is conductive.

At the initial triggering of the time delay device TDS, a positive-goingpulse will be transmitted over the ccnductor 24 to the control grids 325and 326 of the left hand triode section 321 and the riUht hand triodesection 322, respectively, of the trigger circuit 320 in the secondarygate circuit 25. However, the trigger circuit 320 is designed so thatthis positive pulse does not trigger the trigger circuit 320. When thetrigger circuit 310 in the time delay device T133 switches back to itsstable condition, a negative-going pulse is produced in the loadresistor 316 and is fed by the conductor 24 to the control grids 325 and326 of the trigger circuit 320.

This negative-going pulse triggers the trigger circuit 320 into itsalternate stability condition, where the right hand triode section 322is conductive. When the right hand triode section 322 is conductive, thepotential on the control grid 331 of the gating tube 330 is sufficientlypositive that the positive pulses present on the grid 332 from the pulsegenerator 10 cause the gating tube 330 to be conductive. Thusnegative-going pulses are taken from the anode 334 through the capacitor342 and appear across the resistor 341. The negative-going pulses areinverted by the triode discharge device 338 and transmitted through theconductor 2S as positive-going pulses. it is noted that the amplitude ofthe output pulses from the secondary gate circuit 25 may be adjusted bymeans of the variable resistor 341 in the input to the grid 339.

The positivegoing pulses from the secondary gate circuit 25 travelthrough the conductor 2S and the conductors 28 and 2S" to the controlgrids 238 and 234 of the right hand gating tube 235 and the left handgating tube 231, respectively, of the switching means CM. Since theright hand gating tube 235 is partially enabled by the presence of aZero bias potential upon the control grid 237 and the left hand gatingtube 231 is biased olf, the switching means CM functions topreferentially send the positive-going pulses over the conductor 30' asnegative-going pulses to the summation counter S1 instead of to thesummation counter S2 via the conductor 30".

Under these conditions, the counter and butter circuit 14 continues tocount the pulses fed to it through the primary gate circuit 11 and thesecondary gate circuit 25 passes pulses to the summation counter S1. Aspreviously explained, when the counter circuit 14 passes from 09939 to10000, a negative-going Control pulse is transmitted over the conductor34 to the switching device BF and the secondary gate circuit 25. Thisnegative pulse appears on the control grids 325 and 326 of the secondarygate trigger circuit 320 and causes it to change its .ability condition,thereby making the triode section 323 non-conductive and the triodesection 321 conductive. Thus the potential on the control grid 331 otthe gating screens longer continues to pass the positive pulses from thepulse generator 1t?.

The negative-going pulse on the conductor 34 also causes the switchingdevice BF to switch its alternate stability condition, where the righthand triode section 252 is conductive, thereby making the potential onthe conductor 52'? more positive than the potential on the conductor 32and conditioning the summation counters S1 and S2 to operate in aforward direction, as will be explained hereinafter. y

When the secondary gate trigger circuit 320 returns to its initialstability condition, the potential on the anode 324 becomes morenegative and the voltage drop across the load resistor 328 increases.This produces a negative-going pulse on the conductor 35, which iscapacitively coupled to the control grid 215 of the primary gate triggercircuit 210 as well as the control grid 284 of the left hand triodesection 281 of the time delay device TD1 trigger circuit 25). Thisnegative-going pulse appearing on the control grid 215 of the triggercircuit 210, causes the triggercircuit 210 to return toits initialstability condition with the left hand triode section 2H conductive. Inthis initial stability condition for the trigger circuit 210, thepotential on the control grid S of the gating tube 205 becomes lesspositive and the gating tube 205 is disabled. Thus the passage of thepulses from the pulse generator 10 to the counter and buffer circuit 14is blocked.

The negative-going pulse, which appears on the control grid 284 of tneleft hand triode section 281 of the time delay device TD1 triggercircuit 280, triggers the circuit 280 to its unstable condition, wherethe right han triode section 232 is conductive. After a predeterminedperiod of time, the trigger circuit 280 returns to its stable conditionwith the left hand triode section 281 conductive. Upon its return to thestable condition, the anode 283 becomes less positive and a greatervoltage drop appears across the load resistor 23S, thereby producing anegative-going pulse in the conductor 3S.

The negativewgoing pulse in the conductor 38 appears on the control grid305 of the left hand triode section 301 of the time delay device TD2trigger circuit 300 and causes it to switch to its unstable condition.After a predetermined time constant, the trigger circuit 300 returns toits stable condition and a negative-going pulse is produced across theload resistor 306, when the anode 304 and the left hand triode section301 becomes more negative. This negative-going pulse is fed over thecorn ductor 39 to the control grid 214 of the primary gate circuit, andcauses the trigger circuit 210 to switch to its alternate stabilitycondition, thereby increasing the potential of the control grid 208 ofthe gating tube 265 in a positive direction so as to partially enablethey gating tube 205. Thus a new measuring cycle is automaticallyinitiated.

Therefore, it is seen that the switch 221 in the primary gate circuit 11need be actuated only once to initiate the overall operation of theapparatus and from that point on the system automatically resets itself.The resetting of other components of the apparatus will now bediscussed.

It will be recalled that a negative-going pulse was produced in theconductor 38 when the time delay device TD1 returned to its initialstability condition. Besides triggering the time delay device TD2, thisnegative-going pulse is fed over the conductor 38 to the control grids229 and 230 of the double-stability trigger circuit 225 in the switchingmeans CM, and causes the trigger circuit 225 to switch to its alternatestability condition, wherein the left-hand triode section 226 isconductive and the righthand triode section 227 is nonconductive. Thischange in stability condition causes the potential on the control grid237 of the gating tube 235 to become more negative, thereby disablingthe gating tube 235. At the same time, the potential on the control grid233 of the left-hand gating tube 231 becomes'rnore positive and enablesthe gating tube 231 to pass the positive pulses appearing on the grid234 from the conductor 28 over the conductor 30 to the summation counterS2. vThus, the switching means CM is operated to preferentially selectthersummation counter S2 for the next even-numbered measuring cycle.

It will be recaled that when the counter and butter circuit 14 went fromthe count of 09999 lto 10000, a negative-going control pulse appeared onthe conductor 34 and caused the switching device BF to condition thesummation counters S1 and S2 to operate in a forward direction. in orderto return the switching device BF to its initial condition, anegative-going pulse must be fed over the conductor 36 from thetimedelay device TD1 to the control grid 255 of the right hand triodesection 252 of the BF switching trigger 250, which is at this time'vconductive. This is accomplished by means of the triode 294 in the timedelay device TD1. When the time delay trigger circuit 280 returns fromits unstable condition to its initial stability condition, the anode 285of the right hand triode section 232 increases positively in potential,as the right hand triode section 282 becomes non-conductive.

This increase in positive potential of the anode 285 produces apositive-going pulse on the control grid 292 of the triode 294 since thecontrol grid 292 is capacitively coupled to the anode 285. The triode294 then becomes more conductive and the voltage drop across the loadresistor 298 sharply increases, thereby producing a negative-going pulseon the control grid 255 of the right hand triode section 252 of the BFtrigger 250. Thus the BFV trigger circuit 2501 is returned to itsinitial stability condition and the control potential upon the conductor32 is higher than the control potential upon the conductor 32, therebyconditioning the summation counters S1 and S2 for backward operation.

Since the time delay devices TD1, TD2 and TDS are single-stabilitytrigger circuits, they automatically return to their initial stabilitycondition and stand ready for the next cycle of operation. The secondarygate circuit 25 f is also in its initial closed or disabled condition,and is ready for the next measuring cycle.

Returing to the comparator circuits C1 and C2 (FIG. 3), the switchingcircuit CK operates in the following manner to restore the comparatorunits to their initial condition in preparation for the succeeding cycleof operation.

The switching circuit CK, along with the triodes 478 and 478', operatesto extinguish the gaseous discharge devices 421 and 421. Moreparticularly, when either of the gaseous discharge devices 421 or 421 istired and a negative control pulse is placed on the conductor 22 leadingto the time delay device TDS, a negative control pulse is also sent overthe conductor 41 to the control grid 489 of the right-hand triodesection 487 of the CK trigger 485.

In its initial condition, the double-stability trigger circuit 485 hasits right hand triode section 487 conductive and its left-hand triodesection 486 nonconductive. Therefore, when the negative pulse on theconductor 41 is fed to the -control grid 489, the trigger circuit 485switches to its alternate condition of stability. When this occurs, thepotential on the anode 490 becomes more positive, and a positive-goingpulse is transmitted over the conductor 42a, 42 and 4.3 to the controlgrids 480 and 480 of the triodes 47S and 47S'. The triodes 473 and 478ecome highly conductive and draw a large amount of current through theload resistors 425 and 425 of the gaseous discharge tubes 421 and 421.As a result of this increase in current ow through the load resistors425 and 425', the potential on the anodes 422 and 422 is lowered belowthe potential of the cathodes 424 and 424', and the gaseous dischargedevices 421 and 421 are extinguished. Y

Referring now to the time delay device TD2 (FIG. 2), when the triggercircuit 300 returns to its stable condition, a negative-going pulse iscreated in theload resistor 306. This negative-going pulse istransmitted over the conductor 4), as well as the previously mentionedconductor 39, and appears on the control grid 488 (FIG. 3) of theleft-hand triode section 486 of the CK trigger circuit 485. Thus, thetrigger circuit 435 is triggered back to its initial stability conditionfor the start of the next measuring cycle.

iriaving considered the operation of the circuit through an initialodd-numbered measuring cycle, wherein the comparator Cl and thesummation counter Si have been utilized, and the instantaneous sample ofthe variable quantity input has had a negative value, let us nowconsider a second or even-numbered cycle wherein the cornparator C2 andthe summation counter S2 will be utilized. As aforementioned, theswitching means CM is in its alternate stability condition at the startof the even-numbered cycles, so that the comparator C2 and the summationcounter S2 are preferentially selecte Further, let us assume that theinstantaneous sample of the curve ddl has a positive value for thisparticular cycle.

The negative-going control pulse in the conductor 39 (Fl-G. 2)automatically starts the second measuring cycle by triggering theprimary gate trigger circuit 2id, so that the potential on the controlgrid Ztl attains a sutiicient positive value to partially enable thegating tube 295 and allow the pulses from the pulse generator 1i) to bepassed as negative pulses to the counter and buffer circuit 3,4.

Since the instantaneous sample being considered for this cycle isassumed to have a positive value, a coincidence will not be achievedbetween the instantaneous sample and the reference potential or" thetranslator unit before the counter circuit i4 switches from 09999 to10080. However, when the count changes to 10600, a negative controlpulse is fed over the conductor 34 to the switching device and thesecondary gate circuit 25, in the same manner as previously mentionedwith regard to the tirst measuring cycle. The switching device BF isoperated to condition the summation counters Sl and S2 for forwardoperation. Since the secondary gate circuit is still its initial orclosed condition, the negative-going puise on the conductor 34 opens thesecondary gate circuit 25 by triggering the secondary gate triggercircuit 32u. Therefore, constant rep tition frequency, positive pulsesare passed out on the conductor 28 through the lett hand gate tube 23?.of the switching means CM to the summation counter S2.

Since the summation counter S2 is now operating in a forward direction,a count having a value equal to the instantaneous sample of the variablequantity is added to the previous sum on the summation counter S2. Thisis in contrast to the previous cycle where the pulses transmitted to thesummation counter Si, before the counter and butler unit M reached thei086@ count, decreased or subtracted from the count previously on thesummation counter S1.

When the value of the reference potential conductor i9 from thetranslator unit its' rea s equivalent to the instantaneous sample, thegaseous discharge device 421 (FG. 3) is red. A negative-goin pulse istransmitted over the conductor 22 to the time delay device TBE (FG. 2o).This pulse triggers time delay device TDS for a predetermine timeinterval. At the end of that time interval, a negative-going trig rpulse is transmitted from the time delay device TDS over the conductor2K5 to the secondary gate circuit 25 and operates to trigger the triggercircuit 32o, so as to disa'de the gating tube As in the previous cyclewhen the secondary gate circuit 25 is closed, a negative-going pulse isdeveloped across the load resistor and transmitted on the conductor 35to trigger the trigger circuit 21d or the primary gate circuit il,thereby closing the primary gate circuit il. rThis negative pulse on theconductor 3S also serves to trigger the time delay device TDi, whichafter its predetermined time delay produces a negative-going output overthe fed c e a value pulse on the conductor 38 and a positive-goingoutput pulse through the conductor 291 to the control grid 292 ot' thetriode device 294. ln response to the positivegoing pulse, anegative-going pulse is developed across the load resistor 293, which isfed to the control grid 255 of the right-hand triode section 252 of theBF trigger device to return the BF switching device to its initialcondition. rillus, the summation counters S1 and S2 are conditioned forbackward operation in preparation for the next odd-numbered measuringcycle.

The negative-going control pulse on the conductor 3S operates the timedelay device TD2 and triggers the switching means CM to its initialstability condition. Thus, the switching means CM preferentially selectsthe comparator Cl and the summation counter Si for operation durinry thenext odd-numbered cycle. The opera- 'tion of the time delay device TD2by the negative-going pulse on the conductor 33 from the time delaydevice TD1 produces a negative-going pulse on the conductor 559, whichautomatically initiates the next odd-numbered cycle, and anothernegative-going pulse on the conductor 46 which restores the CK trigger485 to its initial condition.

In order to supply the next incremental instantaneous Sample of thecurve lili to the comparator Cl, it is necessary to operate the feedingmechanism 402 (FIG. 3). This is done by means or the electron dischargedevice 492, which, when conductive, energizes the operating coil 497 ofthe feeding mechanism 492.

More particularly, when the time delay device TD1 (FiG. 2a) is operatedby the negative-going pulse on the conductor 35 upon the closure of thesecondary gate circuit 25, the resultant positive-going pulse caused bythe return of the trigger circuit 2813 to its stable condition is passedover the conductor Stltl. Since the control grid 495 (FIG. 3) of thedischarge device 492 in the switching circuit CK is capacitively coupledto the conductor :00 leading to the anode 285 of the TD1 right-handtriode section 232, a positive-going pulse appears on the control grid495 when the TD1 trigger circuit 236 returns to its stable condition,viz., when the left-hand triode section 25a-fl is conductive. Thispositive-going pulse on the control grid 495 serves to partially enablethe discharge device 492.

Since the grid 494 of the discharge device 492 is capacitively coupledto the conductor 499 leading to the anode 228 of the left hand triodesection 225 of the CM trigger circuit, a positive-going pulse willappear on the grid 494 whenever the left hand trigger section is changedfrom a conductive to a non-conductive state. rThis occurs only at theend of even-numbered measuring cycles. Therefore, a coincidence ofpositive-going pulses on the grids 494 and 495 of the discharge device492 will only occur at the end of the even-numbered measuring cycles.When this coincidence occurs, the discharge device 492 becomesconductive and the operating coil 497 of the feeding mechanism 492 isenergized.

Details of the summation counter Referring now to FIG. 4, a plurality ofdouble-stability trigger circuits are cascaded in diterentdenominational banks of scale-of-ten circuits. However, thesescale-often circuits are adapted to operate in a manner different fromthe conventional scale-of-ten circuits, in that they may be conditionedto operate both forwardly and backwardly.

More particularly, each of the summation counters S1 and S2 may comprisetive different denominational banks or orders of scale-of-ten circuits,for example, a units order circuit 556, a tens order circuit 551, ahundreds order circuit 552, a thousands order circuit 553 and a tenthousands order circuit 554. Each of the denominational order circuits55! through 553, inclusive, may comprise tour double-stability triggercircuits 561, 562, 563 and 564, arranged in an identical manner in eachof the order 19 circuits. However, the ten thousands order circuit 554may comprise a single double-stability trigger circuit 561". The triggercircuits 561, 562, 563 and 564cmrespond to the 1, 2, 4 and 8 digits ineach of the denominational orders. Y

Further, each of the trigger circuits 561, 562, 563 and 564 may haveneon indicators or glow tubes :566, 567, 568 and 569', respectively, andresetting means including diode-type electron discharge devices 570,571, 572 and 573, respectively, associated therewith. The diode-typedischarge devices 570 through 573, inclusive, may be individuallyconnected to the'control grid of one triode sec# tion of each of thedouble-stability trigger circuitsfand to acommon conductor 574 leadingto a terminal 575, which may be connected to a suitable reset potentialsource.

A pair of dual triode-type electron discharge devices may be connectedto the load resistors of each of the double-stability trigger circuits561 through 564, inclusive, as .an output means. For example, a pair oftriodes 578 and 579 may be connected to the load resistors 530 and 531associated with the right-hand and left-hand triode sections of thetrigger circuit 561, respectively. The triode discharge device 578 mayinclude an anode 582 and a control grid 583 and the triode dischargedevice 579 may include an anode 535 and a control grid 586. The anodes582 and 585 may each be connected through a common load resistor 590 tothe plate supply bus 201. The control grid 583 of the left hand Youtputtriode 578 may be capacitively coupled to the load resistor 580 of theright hand triode section of the trigger circuit 561. The control grid586 of the right hand output triode 579 may be capacitively coupled totherload resistor 581 of lthe left handtriode section of the triggercircuit 561.l The control grids of the right and left hand triodesections of the neiit trigger circuit 562 may be `capac'itively coupledto the common load resistor 590 for the output triodes 578 and 579. Thecontrol grids 583 and 586l of the output triodes 578 and 579,respectively, may be connected throughv their respective biasingresistors 588 and 589 to the conductors 32" and 32', respectively. I p uA pair of twin output triodes 591and 592 havingv a commonV load resistor594 may be similarly connected between the trigger circuit 562, havingva load resistor 593 inits left hand triode section, and the triggercircuit 563. Another pair of twin triodes 595 and 596 may be coupledvtothe load resistors of the trigger circuit 563 in the same manner as thetwin output triodes 578 and 579 are coupled to the load resistors in thetrigger circuitv 561. However, instead of having a common loadresistor,the triode 595 may haveits own load resistor 598 and the triode 596 mayhave its own load resistor 599. The load resistor 598 of the left handoutput triode 595A may be capacitively coupledrto the control grid vofthe left hand triode section of the'triggercircuit 564, and the loadresistor 599 of the right hand output triode 596 may be capacitivelycoupled tothecontrol grid of the right hand triode section of thetrigger circuit 564.

A load resistor V600'rriay be coupled to the left hand triode section ofthe trigger circuit 564 and another load resistor 601 may be coupled tothe right hand triode sectionV of thetrigger circuit 564. A pair-of dualtriodeei! by a variable tap* to aubiasin'g resistor 614 bridged betweenthe plate supply voltage bus 201 and theY conduc` tor 32". The controlgrid 608 maybe connected to a-V point intermediate two biasing resistors615 and 616v bridged between a conductor 618 leading to the loadresistor 600 of thel trigger circuit 564 and the negative bias# ing bus203. The control grid 608 may also be capacitively coupled through acapacitor 619 to the load resistor 601 associated with the right handtriode section of the trigger circuit 564.

Another pentode-type electron discharge device 624 may be bridgedbetween the conductor 612 leading to the load resistor 593 in thetrigger circuit 562 and the ground return bus 202. The discharge Vdevice624 may have a cathode 625, Va control grid 626, a suppressor grid 628and an anode 629. The suppressor grid 628 may be connected to a variabletap on a biasing resistor 630 bridged between the plate supply voltagebus 201 and the conductor 32. The control grid 626 maybe connected to apoint intermediate two biasing resistors 631 and 632 bridged between theplate supply bus 201 and the negative biasing bus 203. The control grid626 may also be capacitively coupled through the capacitor 634 to theload resistor 600 associated with the left hand triode section .of thetrigger circuit 564.

A variable tap on the resistor grid 626 and the plate supply voltage bus20-1 may be connected by a conductor 635 and a resistor 636'having avariable tap to the negative biasing bus 203. Thus the resistor 636 isplaced in parallel with the portion of the resistor 631, below thevariable tap, andthe resistor Four vtriode-type electron dischargedevices 638, 639, 640 Vand 641 may be coupled between the conductor y635andthe ground return bus'202, and have control grids 642, 643, 644 and645, respectively. The control grids 642, 643, 644 and 645 may beconnected by means of the conductors 646, 647, 648 and 649 to thecontrol grids of the right hand triode sections of the trigger circuits561, 562, 563 and 564, respectively.

A pentode-type electron discharge devicel 650 may be connected betweenthe loadV resistor 598 and the ground return bus 202 in parallelwith theoutput triode 595 of the trigger circuit 563. The discharge device 650may include a cathode 651, a control grid 652, a suppressor grid 654andan anode 655. The anode 655 may be directly coupled to the loadresistor 598 by means of a conductor 656. The suppressor grid 654 may beconnected to the variable tap on the resistor 636. lThe control grid 652may beconnected by a conductor 658 to the control grid 586 of therighthand output triode 579 for the tricger circuit 561.

A triode-type electron discharge device 659 may be connected between theload 'resistor 599 of the right hand output triode 596 of the triggercircuit 563 and the K ground return bus 2 02. The triode 659 maycomprise an type electron discharge devices 602 and 603 havingra ycozrlmon'load resistor 604 maybe arranged asoutput triodes for thetrigger circuit 564 in the same manner.,

sociatedwith the left hand triode section of the trigger i circuitv562;- Thesuppressor'grid '610 may beconnected anode 660 and a controlgrid 661. The anode 660 may be directly coupled to the; load resistor599 by means of a conductor 664.V The controlV grid 661 may be connectedby means of a conductor 662 to the control grid 583 of the left Vhandoutput triode 57S of thetrigger circuit 561.

Thel output loadrresistor 604 of Ythel 8 ydigit trigger circuit 564 ofthe units counting order 550 may be connected to the 7input of thesldigit trigger circuit in the tens order 551 byfmeans of a conductor 665.Similarly, the

output of the intens order' 551` may be connected to the input of theAhundreds order 552by means of a-conductorv 666 and the outputof-'thehundreds order 552 maybe connected to the input of thethousands Y order553'by means of a conductor 667. Y

As shown in FIG.y 4, the ten thousands ordito-#117554may` includevonlythe l'di'gt'trigger cir'cuitf5'61 having a neon vindicator 566'."Vl anda-reset diode 570m?.V vThe trigger circuit 561m may be connected to theoutput of the thousands order 553.193( rneansof a conductor 663.:

631 between the controlv Operation of summation counter Let us nowdiscuss the operation of the summation counter shown in FIG. 4, Aspreviously stated with relation to the operation of the overall system,the switching circuit BF is initially conditioned at the start of eachmeasuring cycle to place the higher potential on the conductor 32' (PEG.2) relative to the ground return bus 292 and the lower potential on theconductor 32 relative to the ground return bus 202. Thus the summationcounters Si and S2 are conditioned to operate backwardly when thecomparators C1 and C2 are operated by a neagtive instantaneous sampie.

However, when the instantaneous sample has a positive value, theswitching device BF, as aforementioned, is switched to its alternatestability condition when the counter 14 reaches a predetermined zeroreference value, i.e. in the preferred embodiment, a count of 1000G. Inthis alternate condition, the potential on the conductor '32" is thehigher relative to the ground return bus 262 and the potential on theconductor 32 is the lower relative to the ground return bus 202. As aresult of the reversal of potential between the conductors 32 and 32,the summation counters S1 and S2 are conditioned to operate in aforwardly direction for positive instantaneous samples.

Let us tirst assume that the summation counter is conditioned to operatein a forward direction, i.e., the potential on the conductor 32 is highrelative to the potential on the conductor 32. Further, let us assumethat the ammation counter has been reset to its initial position. Sincethe summation counter must be able to manifest both positive andnegative sums, it is necessary that a zero value be assumed at a pointintermediate the counting range of the summation counter.

ln the preferred embodiment, the predetermined zero value is assumed tobe when the summation counter is reset to a value of C-00. Such asetting is designated in PEG. 4 by the appropriate shading of theconductive sides of the trigver circuits therein. More particularly, thelett hand triode sections of each of the trigger circuits 561, S62, 553and 56d in the ditierent denominational order banks 550, 551, 552 and553 are initially conductive. However, in the ten thousand order 55d,the right hand triode section of the sole trigger circuit 56 isconductive.

When the secondary gate circuit 25 is opened, at the time that thecounter circuit 14 reaches a count of 10000, negative pulses aretransmitted over the conductor 30 to the control grids of the triggercircuit 561. in this illustration let us assume that a count greater'han l0 is being added to the summation counter Si. The rst negativepulse triggers the l digit trigger circuit 561 to its Ou condition,wherein the right hand triode section is conductive and the left handtriode section is non-conductive. r[he higher potential on the conductor32 relative to the ground return bus 202 is suicient to partially enablethe left hand output triodes 578, 593i, S95, and (db2. The right handoutput triodes 579, 5552, 596 and 603 are disabled, since the potentialon the conductor 32 is insuicient to partially enable the right handoutput triodes, thereby biasing them off.

The change in condition of the trigger circuit 561 produced by the firstnegative pulse over the conductor Sli causes a negative-going pulse tobe produced in the load resistor 58u. Obviously, this negative pulsewhen it appears on the grid 583 of the left hand output triode 578 doesnot render it conductive. On the other hand. a positive-going pulse isproduced in the load resistor 581. However, when this positive-goingpulse is fed to the control grid 586 of the right hand output triode579, it is insuicient to overcome the negative bias on the grid 586.

When the second negative pulse arrives on the conductor 30, the triggercircuit 561 is restored to its initial or `Oif condition. When thisoccurs, a positive-going pulse is produced in the load resistor 53d andcauses the left hand output triode 578 to conduct. Conduction by theleft hand triode 578 causes a negative-going pulse to be produced in theload resistor 59u which triggers the 2 digit trigger circuit 562 to itsGn condition. The third negative pulse merely turns the l digit triggercircuit 561 On.

The fourth negative pulse turns the trigger cuit Sdi Olf and produces anegative pulse across t load resistor 590 which turns the triggercircuit 562 Off. When the trigger circuit 562 is restored to its initialOtt condition, a negative-going pulse is developed across the loadresistor 594, in the same manner as the previously mentioned negativepulses are developed across the load resistor 590. The incominU negativepulses 5, 6, 7 and 8 on the conductor 3i) operate the trigger circuitsSdi, 5a.?, 563 and 564 in conventional counting fashion.

Since the count of 9 is represented by an On condition of the l digittrigger circuit Sol and the 8 digit trigger circuit 564 and an Gticondition of the 2 digit trigger circuit 562 and the 4 digit triggercircuit 563, it is necessary to bias the 2 digit trigger circuit 562 toOil condition, so that the ninth and tenth incominf7 negative pulsesover the conductor 3Q cannot trigger the circuit 562. This blocking isaccompiishcd, when the summation counters S1 and S2 are operating in aforward direction, by means of the pentode discharge device dit?.

With the higher of two potentials on the conductor 32, the Voltage dropacross the suppressor grid biasing resistor 6M is such that thesuppressor grid dit? is at a Zero bias condition, thereby partiallyenabling the discharge device 6%. Yii/hen the trigger tube 55d is in itsinitial Oii condition, the left hand triode section is conductive andthe larger of two voltage drops occurs across the toad resistor 5%,thereby placing the conductor 61S at a lesser potential than when theleft hand triode section of the trigger' circuit Sofi is conductive. lnthis condition, the voltage drop across the resistors @l5 and 616 issuch that the control grid 608 is biased suiiiciently to cut off thedevice 696.

When the trigger circuit 564 is switched to its 0n condition in responseto the eighth negative pulse, the voltage drop across the load resistor@titi decreases and the potential on the conductor SiS becomes morepositive. This serves to increase the voltage drop across the resistor616 and raises the control grid to a zero biasing condition. rFinis thedischarge evice is rendered conductive when the trigger circuit Sed isits Gn condition and the summation counter is operating in a forwarddirection. Since the discharge device otto is conductive, it draws asubstantial amount of current through the load resistor S93 of the lefthand triode sec-- tion of the 2 digit trigger circuit 552, therebybiasing the 2 digit trigger circuit 562 to an OilC condition.

The ninth negative pulse merely serves to switch 0n the l digit triggercircuit Stil'. The tenth negative pulse triggers the l digit circuit 55Eto its initial Oii condition. This change in condition renders the lefthand output triode 578 conductive and a negative-going pulse is producedacross the load resistor 59d, in the usual manner. However, since the 2digit trigger circuit 562 is biased to its Gif condition by thedischarge device 6Go, the negative pulse developed across the loadresistor 59d has no effect upon the trigger circuit 562.

The positive-going pulse produced across the load resistor 580 iscoupled through the conductor 662 to the control grid Gol of the triode659. This positive-going pulse renders the triode 659 conductive andproduces a negative-going pulse in the load resistor 599. Since the loadresistor 599 is capacitively coupled to the control grid of the righthand triode section oi the 8 digit trigger circuit 564, this triggercircuit is switched to its Oli" condition, wherein the leit hand triodesection is conduc tive and the right hand triode section isnon-conductive.

As a' result of this change in the stability condition of conductor 6l8and decreasing the voltage drop across the resistors 615 and 6i6. Thisdecrease in the voltage drop across the resistors 615 and 616 tends tobias the control grid 608 of the discharge device 606 to cut olf.However, at the same time, a positive-going pulse is produced. acrossthe load resistor 6il1 of the 8 digit trigger circuit 564. Thispositive-going pulse is capacitively coupled through the capacitor 619to the control grid dit@ and maintains the discharge device 666conductive Vfor av sufficient time to insure that the 2 digitv triggercircuit 562 is not triggered On as a result of the change in thestability condition of the 1 digit trigger circuit 561.

When the 8 digit trigger circuit S64 is returned to'its initial Offcondition, the left hand output triode 662 is rendered conductive and anegative-going pulse is pro duced in the load resistor 604 which iscarriedV over the conductor 665 to the tens order 551 to trigger the ldigit trigger circuit of that order. el

Thus it is seen that when the higher o is placed on the conductor 32Aand thrglower of two' potentials is placed on the conductnrff'l by thestability condition of the switching device BF, the summation counteroperates forwardly in the same manner as a conventional scale of tencircuit. t

Let us now consider the operation of the summation counter when thepotential on the conductor 32 is at the higher of two potentials and thepotential on the conductor 32 is at the lower of two potentials, i.e.,conditioned by the switching device BF to operate in a back wardlydirection. In discussing this backward operation, we shall assume thatall of the trigger circuits in the summation counter have been reset totheir initial conditions shown in FIG. 4.

The higher potential on Ithe conductor 32 partially enables the righthand output triodes 585, 592,596 and 603. This higher potential alsomakes the potential on the suppressor grid 62S of the discharge device624 more positive so as to bring it toits zero bias condition;V whereas,the lower potential on the conductor 32 lowers the potential on thesuppressor grid 61) of the discharge dielfvice 6426 and biases thislatter discharge device to cut o Since none of the trigger circuits 561,562, 563 or 564 are in an On condition, each of the triodes 638, 639,64) and 641 are biased to cut off. The potential drop across the biasingresistor Y632 'for the control grid 626 of the discharge device 624 isat its highest value -and the control grid 626 is at its zero biaspotential. Thus the discharge device 624 is rendered conductive and thevoltage drop across the load resistor 593 has su'lcient value to biasthe 2 digit trigger circuit 562 to its Git condition. Also the potentialdrop across the resistor636 is at its highest value, andthesuppressor'grid 654 is at a Zero bias potential.

Under these conditions, when the secondary. gate circuit 25 starts topass pulses from the pulsel generator 1G,

the first negative pulse over the conductor 36 vserves toV trigger the ldigit trigger circuit 561 to an On condition. This causes the lett handtriode section of thejtrigger circuit 561 to become non-conductive and apositive-going pulse is developed across the load resistorl 581. Thepositive-going pulse on the load resistor 581 renders the Yright handoutput triode5'i9 conductiveand a negative-going pulse is produced inthe common load resistor 59th However, since the 2 digit trigger circuit562 is biased to its Ott condition by the conductivity of thedischargerde.- vice 624, the negative-going pulse in the load resistor'59a has no effect upon it. 'l

However, the positive-going pulse developed in the load resistor Stil isalso coupled by means of the conductor 65d to the eontroi grid 652 ofthe discharge d'eviceil.y The incidence of the positive pulse uponthecont'rol grid 652 renders the discharge device 656 conductive,thereby' .drawing current through the load resistor 598. Accorr3-` Yingly, a negative-going pulse is produced in' the loadl re-l sistor 598which is c'apacitively coupled to the left hand' triode section offthe 8digit trigger circuit564 and triggers the trigger circuit S64 to its Oncondition. i

This renders the right hand output triode 603 conductive and anegative-going pulse is produced in the load resistor 664 which iscoupled by means of the conductor 665 to the tens order 551. As a resultof this input pulse to the'tens order 55l, the l digit and 8 digittrigger circuits of the tens order are switched tov an On condition anda negative pulse is sent over the conductor 666 to the hundreds order55'2. The hundreds order 552 andthe thousands order 553 are operated inthe saine manner. When the 8 digit trigger circuit of the thousand order553 is operated to its Gn condition, a negativegoing output pulse issent over the conductor 663 to the l digit trigger circuit 561m of theten thousand order 554. This negative-going pulse switches the triggercircuit 5161" to its O condition. Thus the incidence of one negativepulse on the conductor 30 has caused the summation counter to countbachwardly from 19000 to 09999.

ln each ofthe orders 550, 551, 552 and 553, since the l digit and 8digit trigger circuits are in their Cn conditions, the triodes 63S and641 have been rendered conductive. The conduction in these triodesserves to increase the voltage drop across the upper half ofthe resistor'631 and decrease the voltage drop across the resisters 63;?. and l636.This drop in potential across the resistor 632 tends to bias thedischarge dcvice`624 to cutv votii. When this occurs, the dischargedevice 624V becomes' non-conductive the 2 digit trigger circuit 562 isnolonger biased to its Off condition. Thus there is the possi-l bilitythat the negative-going pulse produced in the load resistor 596 in theoutput of the l digit trigger circuit 561 maintaining the Vcontrol grid7626 at its zero bias potential tor a time interval suiiicient tomaintain the 2 digit trigger ycircuit 562 in its @if condition. Y

Thus in contrast to the normal operation of scale of ten circuits,wherein a trigger circuit is only operated after Vthe preceding triggercircuit has gone from an Oil to an On condition and then returned to anOff condition, the higher potential on the conductor 32' serves tocondition the output triodes ofthe trigger circuits so that the triggercircuits will be operated When'the preceding circuit is first switchedAto its On condition. Y

The second pulse incident upon the conductor 30 causes the 1 digittrigger circuit V561 to return to its Orf condition. In accordance withtl e above discussion, thisaction produces no eiect'upon, the 2 digittrigger circuit 5625 because the increase in potential on the controlgrid 583 from the positive-going pulse developed in the Aload resistor580 is insuliicient to overcome the low biasing potential on theconductor. 32". Thus the incidence-of two pulses has caused the unitsorder 550 to manifest a count of 8 and the overall effect uponthesummation counter has been to subtract a count of 2ffrotn the priorcount' manifested bythe summation counter.

, Upon the incidence of a thirdnegtive pulse on the conductor '39, thetrigger circuit is 'switched to its On condition. 1 This causesa'negative pulse yto be` developedV in the Vload resistor 5% which`triggers theV 2 digit trigger circuit 562 to its yOnconditio'npsinceythis latter trigger -v circuitl isfno longer biased to its Oficonditionby the tswitched tofitsl On' condition. 4The'change in the'ystabilityV 25 condition of the trigger circuit` renders "i Y i ducto/eand a nef our output se is de right hand triode and triggers 5 to itsSii condition. Succeeding incomses on the conductor cause the triggerand to operate in a backward count. Further, since 'the right handoutput triodc for the 8 digit trim-cr circuit 55a is partialiy enabiedin pref- 8 digit trigger circuit the circ 7 e@ l() lvence to the iethand output triode 532, a negative outoroduceo in the conductor 665 when64 is switched to On conditionA tion counter of 4 may opn eitherbackward or forward direction under the inriuence the switching deviceEl?, so that the count nianiiested by the counter for each individuaimeasurcycie may either added to or subtracted from the of the countsvmom the previous measuriru7 cycles. Therefore, when the tantancoussamples oi variable quantities are taken constant incremental intervals,the count niariifestv in the summation counters Si and S2 is equal to orproportional to the first order of integration of the variabie quantity.

System for producing o piu/'nitty 0f integration steps T3 t Y a 5""11referring now to sin. are used as in 'Z to a comparator 59d. itranslator unit i5, hereinafter identified may be fed over the conductorto The operation ot the comi arator may stil be regu'ited by tieswitching circuit CM over conductor and the output of the comparator 534may be taken over *be conductor 22 to t1 e time delay it Lil@ sin,

device T53 in the same manner as EEG. i. ad'l ,to tional translator unitT2 may be connected to the su mation counter di by a conduc" r and haveits output connected by a conductor to the cor The buffer it may beeiiminated from the counter eircuit or ter means le. if necessary,convention-ai hunting mea" y be incorporated in the counter cir- .iizeiin-e voltage variations.

The system of FIG. 5 operates in substantially the same manner as thatof FiG. l. .fiore particulariy, when the pri r is actuated at the startof the integrating cycle, pulses are fed from the pulse generator to thecounter ifi. rihe translator Ti provides a reier al equal to orproportional to the count manifested ny e counter it. This referencepotential is fed to the comparator 504. When the reference potentialcoincides value with the instantaneous sample of the variable quantityfrom the source 5M, a control pulse is sent over the conductor 22 andthe time delay device Tg3 to operate the secondary gate circuit 25.Pulses from the puise generator lo are passed through the secondary gatecircuit 25 and the switching means Cit/i to the summation counter ci tobe either added to or subtracted from the prior count manifested by thesummation counter, in exactly the same manner as the puises are eitheradded or subtracted in the summation counter Si in EEG. l. This occursduring the iirst and all odd-numbered cycles of operation in the systemof PEG. 5. The count manifested by the summation counter Si at the endeach individual measuring cycle of the instantaneous sample ot thevariable quantity from the source Sdi is translated by translator' T2into a reference potential, in the same manner that the translator Titranslates the count manifested by the counter 14 into a referencepotential.

The re ace poten ai produced by the translator T2 is then fed to thecomparator 564 during the second and 75 subsequent evennumbered cycles,`as the quantity to which the reference potential from the translator T1is compared. During the second and subsequent even-numbered cycles,count is either added to or subtracted from the summation counter S2 inthe same manner as in FIG. 1. However, the count manifested by thesummation counter S2 instead of being a first order of integration of anindependent variable quantity, is actually a first order of integrationof the individual sums manifested by the summation counter S1 for eachoi the individual measuring cycles. Since those sums are in turn a lirstorder of integration of a variable quantity, it is evident that thecount manifested by the summation counter S2 is equal to or proportionalto a second order of integration of the variable quantity from thesource 501.

Details of the comparator 504 in FIG. 5

in HG. 6, the source 5M of the variable quantity and the comparator 564are shown in detail. Many of the circuit elements and connections shownin FIG. 6 are identical to the eiements of the comparators C1 and C2shown in FIG. 3 and bear the same reference numerals.

The source Sel or" a variable quantity may comprise a piiotogrr icfiirr. 70d having sprocket holes 701 on each side thereof. A curve '782representative of a continuous variable quantity may be placed on thefilm. The area 7&3 to the leit of the curve 752 may be opaque and thearea 7&3 to the right oi the curve 792 may be translucent. A Zeroreference line may be assumed at a position intermediate the sprocketholes TG1, thereby permitting the curve 7d-2 to have positive andnegative excursions representing positive and negative values or" thevariable quantity. The hlm 7% may be driven by the feeding mechanismApparatus for reading the curve 702 may comprise a conventionai cathoderay means 704 having vertical deectic i plates 7de' and horizontaldeflection plates 7&6. The c..ode ray means 76d may be energized by aconentional power supply 7%8, a Vertical deflection control means 7&9and a horizontal deflection control means 710. The horizontal deiiectioncontrol means may be connected to the conductor i9 by means of aconductor 711.

The cathode ray means 794 may be positioned in relation to the 76@ insuch a way that the beam from the cathode ray means 764 is adapted tosweep from left to right across the lm Tiii in a path normal to the zerodatum line and pass through the translucent portion 703' of the iilrn79d. A lens 712 may be placed on the side of the tilm 7th? opposite tothe cathode ray means 794 to collect and concentrate the beam from thecathode ray means '794 upon a conventional photoelectric means 71d. Thephotoelectric means 714 may be connected in series reiation with aconductor 75 and a resistor 716 be? 7een the power supply 763 and theground or referer. e terminal 199. A capacitor 7i8 may connect a pointintermediate the photoelectric means 714 and the resistor fio on theconductor 715 to the negative bias bus 203 through a resistor 719. Theresistor 719 may have a variable tap 720 connected by a conductor 721 toa suppressor grid of a pentode-type electron discharge device 722 havinga control grid 724.

The electron discharge device 722 is comparable to the pentode-typeelectron discharge device 455 of the comparator C1 in HG. 3 and may besimilarly connected to the load resistor dei) and the conductor 22.

The conductor leading from the translator Ti may also be connected by aconductor 726 through the resistor 4&9 to the control grid 420 of thetriode-type gaseous discharge device 425i. The conductor 726 may also beconnected to the smoothing circuit comprising the tetrodc-type electrondischarge device 440 and the capacitor 41.

ri"ne comparator unit may also include the plate to cathode voitagestabilizing circuit comprising the resistive network 448 and thepentode-type electron discharge device 445 as in FIG. 3, yand thequenching tube 478l con- -nected by the conductors 42,y 43 yto ltheswitching circuit tCK.

A pentode-type electron discharge device 728 having :a control grid 729and a suppressor grid 736 may be placed in circuit with the gaseous'discharge Vtube 421 in the same 'manner as 'the pentode-type electrondischarge `devices 455 andV 455 yof the comparators C1 and C2 in FIG. 3with the suppressor grid 730 being capacitively coupled through thecapacitor 452 to the cathode 424 of the gaseous discharge device 423i.

The control grid 724 of the discharge device 722 may be connected to theconductor 31' leading to the right hand side of the switching means CMand the control grid 729 of the discharge device 728 may be connectedthrough the conductor 31 to the left hand side of the switching meansCM. The discharge devices 722 and J728 may be enclosed within a commonenvelope 731 or in separate envelopes.

'Ihe conductor 506 leading from the translator T2 may be connected to acontro-lf grid 735 of a triode-type electron discharge device 736 havingan anode 738 and a cathode 739 and connected as a cathode followercircuit between the high voltage plate supply bus 426 and the groundreturn bus l202. YA cathode resistor 74@ may be positioned between thecathode 739 and the ground return bus 202. The conductor 469 may beconnected to a.

,variable tap on the cathode resistor 744)v and may couple the inputfrom the translator T2 to the control grid 41o" of the pentode-typeelectron discharge device 411.

The discharge device 4H, its associated tetrode-type electron dischargedevice 462 and the voltage regulator means 468 are arranged in circuitWith the gaseous discharge device 421, in the same manner as in thecomparators C1 and C2 of FIG. 3. Accordingly, a detailed discussionofthe control circuits that are identical with those in FIG; 3 will notbe gone into with yrelation to FIG. 6. v

'I'he comparator of FIG. 6 operates in the'following manner. The curve72 represents a continuous variable vquantity having second orderdilerential characteristics.

The horizontal deflection control of the cathode ray means 704 isresponsive to the reference potential developed in the translator T1.

At the beginning of each individual measuring cycle, the beam from thecathode ray means 704'starts to progress from left to right across thefilm 700 as a function of the step-by-step increase of the referencepotential in the translator T1. When the beam becomes coincident withthe curve'702 and passes from the opaque portion 703 '28 device 722 byplacing a zero bias potential upon the control grid 729 through ltheconductor '31"1 l The neww sum that is manifested by the summationcounter S1 is translated by the translator 'lf2 into a signal potentialwhich is carried by the conductor 506 to the control grid 735 of thecathode follower 736. The potential on the control grid 735 causes acontrol voltage to be developed across the `cathode resistor 74E-ti,which is taken by the conductorV 469 to the control grid 410 of thedischarge device 411. The dischargel device 4.11 functions in the mannerdescribed in relation lto FIG. 3 and places a negative bias on thecontrol lgrid 420 that is equal to or proportional to the instantaneoussample, in this case the value of the sum manifested by the summationcounter Sl at the end of the particular measuring cycle.

As described with relation to the system of FIG. 1, the primary gatecircuit 11 is yopened and the counter 14 manifests `an incrementallyincreasing count in response to the pulses from the pulse generator 10.This incrementally increasing count causes a step by step increase of areference potential in the translator T1 which is fed over the conductor19 and the conductor 726 to the control grid 420 of theV gaseousdischarge device 421 When the gaseous discharge device 421 is fired, thepotential of the suppressor grid 738 is raised to a zero bias and anegative control pulse is developed across the load resistor 469 whichis conducted by the conductor 22 to the time delay device TDS. Then, inthe same manner as in the system of FIG. l, a count is either added orsubtracted` in the summation counter S2. Thus the summation counter S2vmanifests a count which is representative of the suni Y of all vtheindividual sums manifested by thesumma'tion counter S1 at the end ofeach measuring cycle.

vThe switching device CK operates to quench'the gaseous discharge tube421 and to cause the feeding mechanism 4%2 to movekthe film 700 in aforward direction by a predeterminedV amount. Since theinstantaneoussamples of the` curve 702 are taken at equal intervalsthe I countmanifested by the summation counter S2 is either equal to orproportional to the value of a dependent Variable of whichthe curve 702is a second order differential.

Thus there has been provided novel and improvedapparatuses forreliablyand rapidly integrating one cr'mo're continuous variablequantities in one or more orders ofy integration.

It will beunderstood by those skilled in the art that theabove-described embodiments are meant to be merely exemplary and thatthey are susceptible of modification and variation without departingfrom the spirit and scope v of the invention. More particularly, it will`be evident that the principles of the invention will be equallyapplicable to the simultaneous integration ofthree or more variable fquantities instead of `merely the two continuous variable pacitor 718 tothe conductor 7l5 produces a positive pulse across the resistor 719.Thisv positive pulse is carried over i the conductor 721 to thesuppressor grid 725V of the discharge device 722. During the initialindividual measuring cycleand subsequent odd cycles,"the switchingmeans' CM `is in such a condition that sutiicient potential is placedVupon the conductor'31 to partially enable the discharge measuringcycle, the .switching means CM operates to par-A tially enable thedischarge device 728 in preference to the quantities illustrated in FIG.l, or three or more orders f of-integration-instead of the two ordersofintegrationA illustrated by the system of FIG. 5.' These types ofmulti- -V ple operations can be accomplished by the utilization ofconventional time-division or multiplex techniques. 'F urther, .it willbe apparent that many other well known types of electronic orelectro-mechanical triggering and measuring devices, which functioninthe samemanner as l"the villustrated components'of the drawings andachieve Y thesame results, may be substituted for the particularelectronic devicesillustrated in the drawings, Ain accordance with theVVinvention. Accordingly, the invention is not deemed to be limited exceptin the manner defined bythe appended claims.

I claim:

. V1. lApparatus for integrating a plurality of instantanei ous valuesof a continuous variabiev quantity represented by a variable electricpotential, comprising a source of' electrical pulses, summation'countermeans capable of totaling the magnitude of al pluralityV ofinstantaneous vvalues and responsive to said electrical pulses forperforming an integration or" the'instantaneous values of saidvariablequantity, gating means connecting said pulse source to said countermeans and adapted to control the flow of pulses therebetween, means forselectively conditioning said summation counter for positive andnegative variations in the setting of said counter, and means responsiveto the magnitude of said instantaneous values of said variable quantityfor enabling said gating means to vary the setting of said summationcounter means as a function of the magnitude of said instantaneousvalues of said variable quantit".

2. Apparatus for integrating a plurality of instantaneous values ot acontinuous variable quantity represented by a variable electricpotential, comprising a source 'of electrical pulses, summation countermeans capable of totaling the magnitude of a plurality of instantaneousvalues and responsive to said electrical pulses for performing anintegration of the instantaneous values of said variable quantity,gating means connecting said pulse source to said counter means andadapted to control the flow of pulses therebetween, means responsive tothe magnitude of said instantaneous values of said variable quantity forenabling said gating means to vary the setting of said summationcounter, and means for reversing the direction of variation of thesetting of said summation counter.

3. Apparatus for integrating instantaneous values of a continuousvariable quantity, comprising a source of electrical pulses having aconstant repetition frequency, register means responsive to saidelectrical pulses, primary gating means interposed between said sourceof electrical pulses and said register means to control the iiow ofpulses therebetween, means for translatinU the setting of said registermeans into a reference signal having au incrementally increasing valueproportional to the setting on said register' means, means for comparingan instantaneous value or" said continuous variable quantity to thevalue oi said incrementally increasing reference value, a summationcounter capable of totaling a plurality of magnitudes of said continuousvariable quantity, a secondary gatint7 means connected between saidsource of electrical pulses and said summation counter, and meansresponsive to said comparing means for enabling said secondary gatingmeans to vary the setting of said summation counter by the addition of avalue proportionate to the instantaneous value of said continuousvariable quantity.

4. Apparatus for integrating the instantaneous values of a continuousvariable quantity, comprising a source of electrical pulses, registermeans responsive to said electrical pulses, primary gating meansinterposed between said source of electrical pulses and said registermeans for controlling the flow of pulses therebetween, a summationcounter capable of totaling a plurality of magnitudes of said continuousvariable quantity, a secondary gating means interposed between saidsummation counter and said source of electrical pulses for controllingthe llow of pulses therebetween, means for enabling said secondarygating means when the setting of said register means reaches apredetermined value, and means for comparing a reference signalproportional to the setting of said register means with a signalrepresentative of an instantaneous value or said variable quantity toclose said secondary gating means when said reference signal is equal tosaid variable quantity signal.

5. Apparatus for integrating the instantaneous values ot" a continuousvariable quantity, comprising a source of electrical pulses, registermeans responsive to said electrical pulses, primary gating meansinterposed between said source of electrical pulses and said registermeans for controlling the iiow of pulses there etween, a summationcounter capable of totaling a plurality of magnitudes ot said continuousvariable quantity, a secondary gating means interposed between saidsummation counter and said source of electrical pulses for controllingthe ilow of pulses therebetween, means for comparing a reference signalproportional to the setting of said register means with a signalrepresentative of an instantaneous value oi said variable quantity toenable said secondary gating means when said reference signal is equalto said variable quantity signal, and means for closing said secondarygating means when said register setting reaches a predetermined value.

6. Apparatus for integrating the instantaneous values of a continuousvariable quantity, comprising a source of electrical pulses, registermeans responsive to said electrical pulses, gating means interposedbetween said register means and said source or" electrical pulses, asummation counter', means for comparing a signal representative of thesetting of said register means with a signal representative of aninstantaneous value or" said variable quantity signal value, and meansfor decreasing the value of comparing means for increasing the value ofthe setting of said summation counter by an amount proportional to theditierence between the value of said variable quantity signal and apredetermined reference value when said predetermined reierence value isless than said variable quantity signal value, and means for decreasingthe value ot the setting of said summation counter by an amountproportional to the difference in value between said predeterminedreference value and said variable quantity signal value when saidpredetermined reference value is greater than said variable quantitysignal value.

7. Apparatus for integrating the instantaneous values of a continuousvariable quantity, comp l ng a source of electrical pulses, egistermeans responsive to said electrical pulses, primary gating meansinterposed between said register means said source of electrical pulsesfor cont-rolling the iiow of pulses therebetween, a summation counter,secondary gating means interposed between said summation counter `andsaid source `of electrical pulses for controlling the flow of pulsestherebetween, means for comparing a signal representative of the settingof said register means with a signal representative of an instantaneousvalue of said variable quantity, means responsive to said register mansand said comparing means for enabling said secondary gating means -toincrease the value of the setting of said summation counter by an amountproportional to the diierence between the value of said variablequantity signal and a predetermined reference value when saidpredetermined reference value is less than said variable quantity signalvalue, and means responsive to said register means and said comparingmeans for enabling said secondary gating means to decrease the value ofthe setting of said summation counter by an amount proportional to thedirierence in value between said predetermined reference value and saidvariable quantity signal Value when said predetermined reterence valueis greater than said Variable quantity signal Value.

8. Apparatus for integrating the instantaneous values o a continuousvariable quantity, comprising a source of electrical pulses, registermeans responsive to said electrical pulses, primary gating meansinterposed between Said egister means and said source of electricalpulses for controlling the dow of pulses therebetween, a surn- Inationcounter, secondary gating means interposed between said summationcounter and said source of electrical pulses for controlling the ilow ofpulses therebetween, means for comparing a signal representative of thesettin g or" said resister means with a signal representative of aninstantaneous value of said variable quantity, means responsive to saidregister means for conditioning said summation counter to operatebackwardly when the setg of register means is less than a predeterminederence value and to operate forwardly when the said re'fister settinghas a value greater than said predetermined reference value, and meansresponsive to said comparing means for enabling said secondary gatingmeans to vary the value or" the setting of said summation counter by anamount proportional to the difference between the

